Abstract

Hydroxy propyl methyl cellulose (HPMC) K4M gels containing free (HCF), liposome encapsulated clobetasol propionate (HCL) and physical mixture of the drug and lipids (HCP) were prepared and subjected to in vitro drug diffusion studies using rat skin to determine diffusion parameters. Data obtained were analyzed to calculate the amount of the drug in the skin (Qm) and the quantity of the drug in the recipient fluid (Csf) and its ratio (Qm/Csf). In vivo skin blanching assay of these formulations in human volunteers showed low blanching scores for liposomal gel formulations indicating low absorption of the liposomal drug in to the blood stream resulting in it's accumulation in the skin. Out of all the formulations tested, liposomal gel prepared with drug, phosphatidyl choline and cholesterol in the ratio of 2:4:1 showed highest Qm/Csf ratio and minimum blanching score.